I've found a vintage piano for sale. From what I can tell, neither the owner nor I are piano experts. Here's what we know:
It's a Wm. Knabe, 6' grand, serial #51504 (1902?) Is there anything particularly good or bad about that vintage of Knabe? Anything unique to this vintage and make that I should look for while giving it the once-over?
The piano is currently white or off-white with light gilding and a stained finish on top. Do you think this is original, or is the paint from a later time?
Well, let's see. If the date is correct the piano is now more than 110 years old. It's a mechanical device. How many 110 year old cars do you see running around?
OK. That's not a fair question; pianos last longer than cars. So how many 55 year old cars do you see running around? Some, but are they in their original condition? Like cars, pianos do wear out but unlike cars they can usually be rebuilt and put back into excellent playing condition by a good piano rebuilder but it may not be cheap. Much depends on what you want out of the piano. If you just want a showpiece to play around with you might get off with just a few thousand. If you want a true musical instrument that will compare with modern instruments I hope your bank balance is in good shape.
Knabe pianos were well built instruments. Often massively built. They tend to hold up reasonably well over time. But unless the action has recently been rebuilt or replaced it's going to be about due. Hard to tell about things like the soundboard and bridges -- depends on where they've been for the past 110 years. If they've spent their whole life in Portland, Oregon there is a chance they are still in adequate condition. Strings will need to be replaced as will the pinblock. (And this may be a difficult block to replace.)
The finish is not original. Most of the old Knabes I've worked on had casework veneered in rosewood. Occasionally a nicely figured mahogany was used. The so-called "antique white and gold" would have been a fashion statement applied during the middle of the last century when it was in vogue to cover up that beautiful veneer work with paint that would then be glazed over to make it look old. Sigh.
The only way you'll know what either the condition of this piano or its potential is to have it examined in person by a competent technician/rebuilder. Everything else -- including what I've written here -- is just guesswork.
Hopefully the piano has not been worked on by an incompetent klutz during its 110+ years of survival. (Although that finish work would cause me to look especially hard for signs of such.) These things started out life with fairly good DNA and they can be wonderful instruments. But you do have to overcome those 110+ years.